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What is it exactly that provides the healing effect of a placebo treatment? (continued)

Peter Slessenger

Reading, Berkshire, UK

The placebo effect relies on the subject knowing that they are taking or doing something, and so some ceremony, however informal, is involved. This wasn’t mentioned in previous answers to this question (21 May).

There are ceremonies for awarding credit, such as graduations, marriages and birthday parties, and for humiliation, such as court hearings. Each has a psychological effect, as does taking a tablet.

I know someone prescribed an SSRI antidepressant in case of stress, who, on experiencing a panic attack, took one tablet and immediately calmed down. As the drugs don’t work that fast, he concluded what he actually needed was a placebo, as the ritual was having the required effect. Knowingly taking a placebo has been shown to reduce the need for medication in treating back pain or IBS.

However, placebos and rituals often have no medicinal effect. One of the most notorious examples is the USPHS Syphilis Study at Tuskegee, which for syphilis. What’s more, the subjects weren’t informed they were part of a study and they didn’t give any informed consent to be part of such a trial. The experimenters wanted to discover how syphilis progressed when untreated, but they acted as if genuine treatments were being provided.

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